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LIGHT METALS AND CARBON MATERIALS
ArticleName Electrochemical production of aluminum hydroxide, including the removal of iron from aluminum chloride
DOI 10.17580/tsm.2018.05.05
ArticleAuthor Lysenko A. P., Kondrateva E. S., Shilovskiy S. Yu.
ArticleAuthorData

National University of Science and Technology MISiS, Moscow, Russia:

A. P. Lysenko, associate professor of the Department of Non-ferrous metals and gold, e-mail address: reikis@yandex.ru
E. S. Kondrateva, post-graduate student of the Department of Non-ferrous metals and gold
S. Yu. Shilovskiy, Researcher of the Department of Non-ferrous metals and gold

Abstract

The possibility of applying acid methods for the processing of kaolin clays, which are the raw material for the production of metallurgical alumina, is analyzed. Moreover, the technology of separation of aluminum and iron chlorides by the salting out method is investigated. A number of significant shortcomings were revealed. A method for electrochemical purification of the aluminum chloride solution from iron with possible regeneration of hydrochloric acid is proposed. The requirements for the electrode materials are analyzed. The electrochemical process of decomposition of an alumina chloride solution with formation of chlorine, hydrogen and iron on the corresponding electrodes is investigated. The behavior of chlorine during electrochemical decomposition of an alumina chloride solution is analyzed. Laboratory studies of the purification process of the alumina chloride solution showed that increasing the anode current density from 0.01 to 0.1 A/cm2 enables to achieve a yield of 98% chlorine flow. The possibility of secondary reactions at the anode with the formation of oxychlorides of the type Al2(OH)nCl6 – n was revealed. Technological solutions that allow controlling the anode process and eliminating the possibility of formation of Al2(OH)nCl6 – n are proposed. Optimal regimes and parameters of the electrochemical purification process of the alumina chloride solution are presented. It was revealed that the greatest efficiency of the purification process of the alumina chloride solution occurs at the cathode current density of 0.01 to 0.15 A/cm2. A schematic diagram of an apparatus for producing aluminum hydroxide by an electrochemical method is proposed. The apparatus consists of an electrolysis bath, a preparatory and a collection tank. The steel and titanium electrodes were introduced into the bath to perform the electrochemical task. The required temperature was set and maintained using a flow heater. The acidity and temperature of the solution were conti nuously monitored. The laboratory investigations of the electrochemical purification of alumina chloride solutions revealed the possibility of obtaining aluminum hydroxide with a residual iron content of less than 0.005% in the solution.
The work was carried out with the financial support of the Ministry of Education and Science of the Russian Federation within the framework of fulfilling the obligations under the Agreement on granting a subsidy from November 02, 2015 No. 14.581.21.0019 (code “Glinozem”).

keywords Electrolysis, kaolin clay, aluminum chloride solution, laboratory tests, acid method, aluminum chloride, electrochemical decomposition
References

1. Layner Yu. A. Alumina production. Achievements in science and technology: Metallurgy of non-ferrous and rare metals. Мoscow : VINITI AN SSSR, 1979. Vol. 12. 80 p.
2. GOST 30558–98. Metallurgical Alumina. Technical specifications. Introduced: 01.07.2000. Мoscow : Publishing Standards. 2000. 2 p.
3. Valeev D. V., Layner Yu. A., Vompe T. S., Pak V. I. Separation of aluminum and iron chlorides by salting out. Proceedings of the Samara Scientific Center of the Russian Academy of Sciences. 2014. Vol. 16, No. 4 (3).
4. Valeev D. V. Physicochemical basis for the teaching of alumina and mixed coagulants from boehmite-kaolinite bauxites with hydrochloric acid autoclave leaching. Dissertation of Candidate of technical sciences. Мoscow: MISiS. 2016.
5. Moskvitin V. I., Nikolaev I. V., Fomin B. A. Metallurgy of light metals. Мoscow : Intermet Engineering, 2005. 416 p.
6. Jones J. L. Process of preparing aluminum chlorhydroxides and aluminum hydroxide. Patent 31391 US. Published: 1963.
7. Bergner D., Danner M. Process for preparing basic aluminum chlorides. Patent 4203812 US. Published: 1980.
8. Konig J., Platzer H. K. Process for the manufacture of water-soluble basic aluminum compounds. Patent 3240687A US. Published: 1966.03.15
9. Lysenko A. P., Kondrateva E. S., Nalivayko A. Yu. Development of a method for purifying aluminum-chloride solutions from iron by electrochemical method. Non-ferrous metallurgy. 2016. No. 4. pp. 28–33.
10. Lysenko A. P., Kirov S. S., Tarasov V. P., Nalivayko A. Yu., Kondratyeva E. S. Method for purification of aluminum chloride solutions. Patent 2625470 RF, MPK С 01 F 7/62, C 01 F 7/20, C 22 B 3/10. Patent holder: FGAOUVO NITU MISiS. Published: 2017.07.14
11. Zhang T., Han X., Lv G. et al. Research on alumina preparation from aluminium chloride solution by electrolysis process. Light Metals. 2018. pp. 97–103.
12. Lysenko A. P., Nalivayko A. Yu., Kondrateva E. S. Application to patent 2017123106 RF. 2017.06.30.

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